Returns a copy of the valarray object with its elements shifted left n spaces (or right if n is negative).

The valarray returned has the same length as *this, with the new elements value-initialized.

By shifting a valarray, the I-th element in the resulting valarray corresponds to the I+n-th element in the original valarray (whenever I+n is less than its size) or a default-constructed element (if I+n is greater than the size).

Unlike valarray::cshift (circular shift), the valarray returned by shift does not include the first n elements in *this (or the last -n elements if n is negative) in any position.

Parameters

n

Number of elements to shift. If positive, it is shifted left. If negative, it is shifted right.

Return value

A new valarray object with the elements of *this shifted n spaces left.

Iterator validity

Data races

Exception safety

If the function implementation assigns to elements, and any such operation throws an exception, it causes undefined behavior.
If the function needs to allocate internal storage and fails, it may throw an exception (such as bad_alloc), although this is not mandated.